[This exists as a comment to Clint's writing below; since I can post normally I thought I'd do that]
This fine paper, seen by this reader for the second time around (!), addresses many of the fundamental issues. However it lacks the following, which would augment the demand for the end to filioque:
1. Relations of origin. Persons in basic Eastern trinitarian theology are defined by whence they come. Thus the Son is so defined by being the Son of the Father and the Spirit likewise. This is a one way definition reflecting the majority report on the relationsihp between time and eternity. Filioque is part and parcel to this definition and does not, as Clint's essay suggests around the edges, view the Spirit's all together new role vis-a-vis the Father and Son. In other words, the action towards the other persons is not from eternity to eternity but from the eschatological life of the future of God. God has time and God has time as God the Spirit.
2. A one-sided objection to the filioque as an imposition on the East denies the truth it does have. Moltmann's formulation makes me unconfortable because it points to a way that the Son and the Spirit's eternal action is detached from the action and identity they have in time. In the biblical witness the Spirit is sent by Christ. Thus, there is no easy symmetrical order as Moltmann would wish. Rather, the diversity of actions and "sendings" should be respected. How could Moltmann understand the sending of the Spirit by the Son? Such an action in the economy does not correspond to an eternal action of God. After all, it is my convication that there is no divine being or action that is evangelically valuable (everything else is the hidden God) outside of the gospel action of the persons in the biblical witness and thereofre in history
Thus, even though the West's view is an innovation and should not have the sort of authority that the original creed does, the West's views should be valid local interpretation. Thus, the filioque is recognized and limited and expanded with thinking like Clint's view if my caveat is valid.